Roof jets



1.. D. GIGANTINO ETAL I 3,337,204

ROOF JETS Aug. 22, 1967 Filed Dec. 24, 1

. 6 Z 0 4 5 vm 5 4mm 5 m J MIAIRVK l ll n m fl mfv m Z 0 w] F lvli If 3 AW ill I n /A m. I 0 H W v INVENTORS GANTINO GANTINO ma? ATTORNEY United States Patent 3,337,204 ROOF JETS Leonard D. Gigantino, Maplewood, and Ottoue M.

Gigantino, Newark, N.J., assignors to Union Carbide Corporation, a corporation of New York Filed Dec. 24, 1964, Ser. No. 421,052 1 Claim. (Cl. 266-34) This invention relates to metallurgical lances, and more particularly to roof jets employing oxygen for refining molten steel.

Briefly, the invention provides a roof jet having a multiorificed, hollow tip of metal in which an individual post is provided within the tip for each oxygen orifice. Such posts are connected to a baflle in the form of an inwardly projecting annular flange having an inlet opening through which cooling liquid flowsfirst against the end wall of the tip, then outwardly under the baffie about the posts, and finally upwardly behind the posts through guide slots in the flange. Such slots are critically located adjacent the surfaces of the posts that are farthest away from the center of the tip so that the liquid in flowing through the slots must flow over such surfaces, As a result, forceflow of the cooling liquid takes place in the most critical areas of the tip, greatly increasing the useful life of the lance.

The main object of this invention is to increase the useful life of metallurgical lances without increasing the cost thereof.

Another object is to provide a roof jet employing oxy-' gen for refining molten steel that is simple, yet economical in construction, light in weight, and is highly effective in reducing the overall cost of making steel as a result of having a relatively long life.

Such objects are accomplished by the novel cooling water bafile adjacent to the annular side wall of the hollow water-cooled tip, that has no water exits 'exeeept for the water guiding exit slot-s that are critically located adjacent areas of posts containing the oxygen exit passages. In the present case, the baflie is impervious except for such slots so that all of the water is forced to flow through the novel outlet slot-s that are located in the baflle adjacent such areas. This markedly improves the efliciency and effectiveness of the cooling water in the critical zones adjacent the corners of the oxygen post walls and the end face of the tip.

In the drawings:

FIGURE 1 is a fragmentary vertical cross-sectional view of a metallurgical lance embodying the invention, taken on line 1-1 of FIGURE 2; and

FIGURE 2 is a transverse cross-sectional view of the tip of the lance taken on line 2-2 of FIGURE 1.

As shown in such drawing, the lance comprises a hollow tip 12 that is composed of copper and/or alloys thereof, having an end wall 14 and an integral annular side wall 16. The outer face 18 of the end wall 14 is flat in the present example, but may be conical; and the inner surface 20 thereof is substantially concave. The end wall 14 is provided with upwardly and inwardly inclined integral posts 22. The mid-portions of posts 22 are integral with an annular flange 24 that extends inwardly-horizontally from the annular side wall 16. The flange 24 constitutes an annular baflle that is impervious except as noted below. The flange 24, in turn, is in the illustrated 'ice example integral with such side wall 16, and is vertically spaced upwardly from the end wall 14, providing a chamber 26 within the tip.

Each post 22 contains a reactive fluid discharge passage 28 for discharging oxygen for example, from the tip 12. The fluid dis-charge passages 28 are equally spaced from one another in an annular row about the vertical axis of the lance, with their longitudinal axes extending downwardly and outwardly from a common point on such axis. While six posts are shown, any desired number may be used. The passages 28 in the posts are all supplied with oxygen through a gas inlet chamber in communication with the common tubular passage 30 between an inner pipe 32 and an intermediate pipe 34 that are connected to upstanding flanges 36 and 38 on the transverse flanges 24 by silver solder, for example.

Water is supplied downwardly to the chamber 26 in the tip through inner pipe 32 and water inlet chamber provided by the central opening 40 within the inner rim 42 of the flange 24. Such water fills the chamber 26 and flows outwardly around the posts 22, under the flange 24, then exits upwardly through arcu'ate slots 48 in such flange 24. A slot 48 is associated with each post 22 and is critically located so that the cooling water having nowhere else to go is forced to flow upwardly behind each post, leaving the tip by way of a common water outlet chamber provided by the tubular space 50 between the intermediate pipe 34 and an outer pipe 52. The lower annular edge of pipe 52 is welded at 54 to the annular upper rim of side wall 16 of the tip 12.

Thus, in use, when the lance 10 is lowered into a steel making furnace, and oxygen gas is discharged from the ports 28 for reaction with the molten steel bath, cooling water flowing continuously through the chamber 26 of the tip 12, keeps the face 18 relatively cool, even though the latter is subjected to the intense heat resulting from such reaction. The useful life of the tip, especially in the critical zones adjacent the corners of the walls of the ports 28 with the end face 18 of the tip, is greatly extended by virtue of the novel flow of the cooling water in the areas behind the posts 22, as such water leaves the chamber 26 through the slots 48.

The tip may be cast or forged, and the slots 48 may be shifted from the positions shown with respect to the posts, as may be desired to obtain the maximum benefit of their function, without departing from the invention. Also, the inner surface of the end wall may be provided with cusps and/or vanes, as may the downstream sides of the posts.

What is claimed is:

A metallurgical lance comprising a hollow water cooled tip having an end wall, an integral annular side wall, an outer pipe connected to such side wall, said tip also having an annular baflle extending inwardly in a substantially horizontal direction fromsaid side wall and providing a central water inlet chamber, an inner pipe and an intermediate pipe connected to such baflle to provide an annular gas inlet chamber, said tip having a plurality of posts extending between and integral with said baflie and end wall, said posts having reactive gas discharge passages leading from the gas inlet chamber, and said baifle having water exit slots only in areas adjacent of said posts for guiding cooling water supplied by said inner pipe through the central water inlet chamber to the interior of the tip under said baffle, and upwardly adjacent the resulting post surface areas between the posts and said side wall, to thereby maintain relatively cool the critical zones of tip at the corners of the reactive gas discharge passage walls with the outer face of said end wall, said outer and intermediate pipes providing a water outlet passage in the space therebetween which is in communication with a common water outlet chamber in communication with such slots. 

